10 years at the helm of the blogging service, he said on Monday

Tumblr founder and CEO David Karp will step down after more than 10 years at the helm of the blogging service, he said on Monday.

"My decision comes after months of reflection on my personal ambitions, and at no cost to my hopefulness for Tumblr's future or the impact I know it can have," Karp said in a letter to staff.

Tumblr is part of Verizon’s Oath business, which houses Yahoo and AOL internet properties.Yahoo bought Tumblr for $1.1 billion in 2013.